Bleed air from an axial flow compressor flows through axis-symmetric slots in an inner casing to a manifold. The bleed air in the manifold is directed to at least one of an aircraft environmental control system or wing-anti ice system, or elsewhere in the gas turbine engine for cooling. Flow extractions from the manifold at discrete locations can cause uneven pressure distribution and create a non-axis-symmetric bleed flow from the compressor. A non-axis-symmetric flow results in lower compressor stall margins than an axis-symmetric flow. Flow asymmetry can be reduced by decreasing the area of the bleed slots, but this can cause an increase in pressure losses.